1 /*
2 * Copyright (C) 2016 Oracle. All Rights Reserved.
3 *
4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it would be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
19 */
20 #ifndef __XFS_REFCOUNT_H__
21 #define __XFS_REFCOUNT_H__
22
23 extern int xfs_refcount_lookup_le(struct xfs_btree_cur *cur,
24 xfs_agblock_t bno, int *stat);
25 extern int xfs_refcount_lookup_ge(struct xfs_btree_cur *cur,
26 xfs_agblock_t bno, int *stat);
27 extern int xfs_refcount_get_rec(struct xfs_btree_cur *cur,
28 struct xfs_refcount_irec *irec, int *stat);
29
30 enum xfs_refcount_intent_type {
31 XFS_REFCOUNT_INCREASE = 1,
32 XFS_REFCOUNT_DECREASE,
33 XFS_REFCOUNT_ALLOC_COW,
34 XFS_REFCOUNT_FREE_COW,
35 };
36
37 struct xfs_refcount_intent {
38 struct list_head ri_list;
39 enum xfs_refcount_intent_type ri_type;
40 xfs_fsblock_t ri_startblock;
41 xfs_extlen_t ri_blockcount;
42 };
43
44 extern int xfs_refcount_increase_extent(struct xfs_mount *mp,
45 struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec);
46 extern int xfs_refcount_decrease_extent(struct xfs_mount *mp,
47 struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec);
48
49 extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp,
50 struct xfs_btree_cur *rcur, int error);
51 extern int xfs_refcount_finish_one(struct xfs_trans *tp,
52 struct xfs_defer_ops *dfops, enum xfs_refcount_intent_type type,
53 xfs_fsblock_t startblock, xfs_extlen_t blockcount,
54 xfs_fsblock_t *new_fsb, xfs_extlen_t *new_len,
55 struct xfs_btree_cur **pcur);
56
57 extern int xfs_refcount_find_shared(struct xfs_btree_cur *cur,
58 xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno,
59 xfs_extlen_t *flen, bool find_end_of_shared);
60
61 extern int xfs_refcount_alloc_cow_extent(struct xfs_mount *mp,
62 struct xfs_defer_ops *dfops, xfs_fsblock_t fsb,
63 xfs_extlen_t len);
64 extern int xfs_refcount_free_cow_extent(struct xfs_mount *mp,
65 struct xfs_defer_ops *dfops, xfs_fsblock_t fsb,
66 xfs_extlen_t len);
67 extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp,
68 xfs_agnumber_t agno);
69
70 /*
71 * While we're adjusting the refcounts records of an extent, we have
72 * to keep an eye on the number of extents we're dirtying -- run too
73 * many in a single transaction and we'll exceed the transaction's
74 * reservation and crash the fs. Each record adds 12 bytes to the
75 * log (plus any key updates) so we'll conservatively assume 32 bytes
76 * per record. We must also leave space for btree splits on both ends
77 * of the range and space for the CUD and a new CUI.
78 */
79 #define XFS_REFCOUNT_ITEM_OVERHEAD 32
80
xfs_refcount_max_unmap(int log_res)81 static inline xfs_fileoff_t xfs_refcount_max_unmap(int log_res)
82 {
83 return (log_res * 3 / 4) / XFS_REFCOUNT_ITEM_OVERHEAD;
84 }
85
86 #endif /* __XFS_REFCOUNT_H__ */
87